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When converting date, I get previous day

I want to convert a string into a date "as it is".
const date = "8/16/2019"
console.log(new Date(date))
However, I get:
As you can see I get the prevous day. I was thinking that it might be a timezone issue, even though there is no timezone that I am converting it from.
Any suggestions how to convert is as it is?
I appreciate you replies!

If your format is consistent, you could split on / and use Date.UTC. Creating your new Date from that would ensure it's UTC.
const date = "8/16/2019"
const [month,day,year] = date.split("/");
const utcDate = Date.UTC(year,month-1,day);
console.log(new Date(utcDate));

const date = "8/16/2019"
console.log(new Date(date).toLocaleString("en-US", {timeZone: "Asia/kolkata"}))
Note:- You need to add timezone

You can use toLocaleDateString
console.log(new Date("8/16/2019").toLocaleDateString('en-us', {timeZone: "Asia/Kolkata"}))

new Date("8/16/2019") will create a date object using your current timezone. Add a "Z" at the end if you want your date to be in UTC.
console.log(new Date("8/16/2019Z"))
EDIT
It appears that Firefox is not implementing the parsing of standard date format. Unfortunately until recently how exactly was a date parsed was completeley based on heuristics and intrinsically non portable.
Looking at Firefox bug tracker seems the issue has been discussed but the problem is still present (some toolkit just works around by replacing "Z" with "+00:00" before calling the parser).
The only way to be sure on every browser is to parse the string yourself and build the date from the fields. I didn't notice because I'm using chrome instead (in both chrome and Node works as expected).
EDIT 2
After more investigation seems the standard requires that:
If you use yyyy-mm-ddThh:mm:ssz then you get what ISO format for datetime defines it to be. Also the syntax described in the standard is not very precise and for example is not clear to me if the time zone can be present when no time is present (Chrome says yes, Firefox says no).
If you use another format then anything goes (so for example there is no string that is guaranteed to issue an invalid date response).
In other words new Date("8/16/2019") is not portable Javascript (with the meaning that you don't know what date / time / timezone you will get, if any). Either you parse yourself the date or you just live with what that version of that Javascript engine in that moment decides to give you.

Moment.js 2 different date strings when i parse using moment gives same value

I am parsing 2 different date strings
var d1 = '2014-02-01T00:00:00.000+0530'
var d2 = '2014-02-23T00:00:00.000+0530'
when i parse them using moment
alert(moment(d1, 'YYYY-MM-dd"T"HH:mm:ss.fffffff"Z"').toDate());
alert(moment(d2, 'YYYY-MM-dd"T"HH:mm:ss.fffffff"Z"').toDate());
both of them print Sat Feb 1 2014 xxxxx
what is wrong with it??
here is the link to the fiddle i created
jsfiddle

I think your moment formatting string is causing you the problem. If I remove this, the dates do not print as the same.
http://jsfiddle.net/K5ub8/7/
EDIT: The specific issue is you are using dd for day, instead of DD. http://momentjs.com/docs/#/parsing/string-format/
Here is your fiddle fixed:
http://jsfiddle.net/K5ub8/9/
However, I am not 100% sure about the fractional seconds, I believe it is SSS instead of fffffff but I would test this if you need to cater for fractional seconds.
I should mention that if you are converting it back into a JavaScript date object anyway with toDate(), then you don't really need the moment formatting parameter as the date will be formatted in JSON Date format.
I would question why you would want to generate a moment formatted date, and then convert it back to JavaScript, a normal practice might be to receive a date in JavaScript format, then create a moment object which you can use to perform calculations and display in a nice user friendly way.

Simple answer: your format was off a bit.
http://jsfiddle.net/K5ub8/8/
After tweaking the format to be 'YYYY-MM-DDTHH:mm:ss.SSSZZ' rather than 'YYYY-MM-dd"T"HH:mm:ss.fffffff"Z"' it worked just fine. When you're trying to debug issues like this, it's always good to keep the format in a separate variable so you can use the same format that you're trying to parse out to display what you're getting. Had you done that, you would have noticed that 'YYYY-MM-dd"T"HH:mm:ss.fffffff"Z"' was messed up due to it printing out 2014-01-Fr"T"11:32:03.fffffff"-08:00". Which obviously isn't quite right.

JSON date, display original date in the server's timezone

For example, I have a string date like this (I'm getting this from the server in json, from rails app)
s = "2013-09-01T00:00:00.000+08:00"
I would like to display it like so
01.09.2013
So I'm using moment.js library for this
moment(s).zone("+08:00").format("DD.MM.YYYY")
>> "01.09.2013"
But I don't know if needed timezone is +08:00. If I skip .zone() call, result would be wrong because my browser is in differnt timezone
moment(s).format("DD.MM.YYYY")
>"31.08.2013"
Even though in my original string I had +08:00 at the end.
So, my question is how can I extract time zone from json date string using pure javascript or moment.js library?
The simplest way I can think of is extracting the last 6 characters manually,
s.slice(s.length - 6, s.length)
> "+08:00"
But maybe there is a better approach for this task?

Just use the parseZone function, like so:
moment.parseZone(s)
Documentation is here.
Alternatively, you can use the older approach, which does the same thing:
moment(s).zone(s)

Trying to parse date using new Date(). but keep getting wrong results

I am trying to parse a date string i get from php through ajax call(which is irrelevant for now) using new Date().
however i keep getting wrong results.
My string is 2013-05-09 20:56:17
When i do
var something = new Date("2013-05-09 20:56:17");
alert(something.getMonth());
It keeps alerting 0
In my opinion for some reason new date cant parse this string.
Is there a way to specify the date format for new Date() in JS ?
My current solution is to import php's: date() and strtotime() and use them :
alert(date('m', strtotime("2013-05-09 20:56:17")));
This works however I have to use external js lib and I am pretty sure there is a better JS way to achieve that.

If you use slashes instead of hyphens, it works:
var something = new Date("2013/05/09 20:56:17");
alert(something.getMonth());
It's easy enough to replace any hyphens in a string with slashes first if you need to (say, if you were getting the date string from somewhere else):
var something = new Date("2013-05-09 20:56:17");
something = something.replace('-', '/');
It seems JavaScript's Date constructor doesn't recognize date formats with hyphens, or at least not that particular format.

Choose a different format specifier in PHP for your ajax dates. The format you expect and the format expected by the javascript are different.
var something = new Date("2013-05-09T20:56:17");
Note the 'T' which appears as a literal separator and marks the beginning of time per ISO 8601
Reference for various [browser] javascript date formats
W3 DateTime
Microsoft IE DateTime
Mozilla [Firefox] DateTime
Google DateJs
And lastly, the PHP date format specifier list:
PHP Date
PHP DateTime
Note the 'DATE_ISO8601'; but I suggest not using that at this time. Instead use 'DATE_ATOM' which may produce a date format more widely supported (comments suggest it makes iPhones happier and no issues with other browsers).
To use it in PHP:
$something = new DateTime('NOW');
echo $something->format('c');
echo $something->format(DateTime::ATOM);

JSON datetime between bash script and JavaScript

In the same spirit as discussed here, is there a recommended way to generate / parse dates from within a bash script so that it can be interfaced to Javascript Date?
To be precise, I get this strings when doing json encoding of a Javascript Date object:
2011-10-31T10:23:47.278Z
I could put together a bash hack to generate / parse that date format, but I would prefer to avoid reinventing the wheel. Does somebody have a working solution?
I am more interested in the "generating" side: I want to generate current dates from a bash script and save them in a json document (couchdb) so that they can be automatically ordered by the view engine.

The closest I am coming is this:
date -u +"%FT%T.000Z"
Which gives this output:
2011-11-03T06:43:08.000Z
I do not like that I have to put the T, the Z and the milliseconds to 0 manually (I can use %N for nanoseconds, and truncate with sed or whatever, but seems like overkill just to get millisecond precission), and I was hoping that there would be a built-in format token for date which would produce that UTC date. I assumed - wrongly it seems - that the format is common enough that it can be specified with just one format token.

JavaScript can convert many different values into dates. Not sure if that's what you mean, but for example. Your bash could generate this string: "2011/11/10 08:08:08"
When it gets to JavaScript land you can do this
var date = new Date("2011/11/10 08:08:08")
You can also do this:
var now = 1320287813362
var date = new Date(now)
More info on what Date accepts here:
https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Date
Other interesting info here:
What's the best way to store datetimes (timestamps) in CouchDB?